Peter E Marshall , Luke E Faggetter, Mike Widdowson

The Kalkarindji continental flood basalt province of Northern Australia is the oldest basaltic LIP in the Phanerozoic having erupted in the mid Cambrian. At this time, during the Cambrian Explosion, the global environment suffered a series of mass extinctions and biotic turnover. Kalkarindji had the potential to release 1.65 x 106 Tg of CO2, approximately 1.72% of the total Cambrian atmospheric carbon reservoir. It has therefore been implicated as a driver of the environmental changes in the Cambrian Series 2. However, temporal discrepancies between Kalkarindji eruptions and biotic turnover may prevent this LIP from being attributed as the sole cause of the Botomian-Toyonian Extinction, which wiped out up to 45% of all genera in the fossil record; whilst environmental factors such as sea-level change causing ocean anoxia are implicated in the Redlichiid-Olenellid Extinction. It is certainly possible that Kalkarindji could have played a part in forcing these environmental changes, but further advances in geochronology and sedimentary volcanic proxies are needed to confidently define a direct causational link between these events at the dawn of the Phanerozoic.